Zombieman

The zombieman (also called the former human in the game manuals, and often referred to colloquially by the Doom community as the trooper) is the least powerful enemy in the game, intended as the first enemy a new Doom player will face. A zombieman is described as a space marine which has been turned into a zombie during the invasion from Hell. The monster appears as a man in a bloodied tan uniform and body armor, carrying a rifle. His hair has an unusual greenish tinge, perhaps stained with nukage, reminiscent of the odd hair colors that often occur in comic books, anime, and animated works of art. He is officially described as such: "Just a few days ago, you were probably swapping war stories with one of these guys. Now it's time to swap some lead upside their head."

- Doom instruction manual

Combat characteristics
The zombieman will make one of three different sounds when alerted: an animalistic roar, or two inarticulate chatter sounds. All three zombie types make the same sounds when they spot the player. The zombieman is armed with a rifle that fires bullets that are slightly less damaging than the player's bullets. When the zombie attacks, it aims its rifle at the player for a short time (10 tics) and fires a single pellet. The zombieman's weapon has a wide dispersal (standard deviation around 9&deg;, to a maximum of ±22&deg;), and will most likely miss at medium to long ranges. After firing, the monster resumes walking to its target.

The zombieman is generally considered the least dangerous enemy in the game; no other monster (excepting the Commander Keen) has a lower movement rate, hit point total, or average damage per attack. When killed, the zombieman falls hard on its back with various bits of blood and flesh blown off its form, dropping an ammo clip containing 5 bullets (or 10 on I'm too young to die and Nightmare!); if he subsequently respawns or is resurrected, the zombie will drop another clip each time it is killed again. It can also be gibbed if attacked with powerful weaponry, such as a rocket launcher.

Tactical analysis
Unless in poor health, an armed player should never need to back down from a single zombieman, although large groups can slowly drain the player's health during the time it takes to kill them all (as in Evilution MAP09). The dispersal of the shots from its rifle means that it is barely a threat at medium to long ranges. In an emergency, or when conserving bullets during a Tyson run, the fist is effective in the short term if the player's footwork is good (two blows will usually knock one down, while a single berserk attack will certainly finish it, often gibbing it). As they are extremely weak and easily disposed of, using heavier weapons against them is considered a waste.

Zombiemen, and other low-ranking monsters, can be used as a form of "roadblock" to slow down the player, usually through the use of teleport traps. While relatively easy to handle during normal play, this tactic may be used by mappers to frustrate speedrunners.

Zombiemen hordes may also serve as to cause confusion between the player's weapons and the player's intended target. An example setup is a higher-ranking monster attacking from a raised platform distant from the player, with zombies swarming in the foreground. It is best to take care of these zombies as soon as possible, as waiting on infighting may waste valuable health and time, especially if other monsters can reach you with projectiles.

The zombieman's low rate of fire and damage capability make it a rather weak contributor to monster-monster battles. Attrition among a crowd of zombiemen is generally slow, and distraction of larger monsters minimal.

In most stock levels, many of the enemies in the first few rooms are zombies. Unless the player's primary goal is speed, the zombiemen's dropped clips can be a valuable early source of ammunition. In most cases, ammo gained from picking up a clip dropped by a zombieman will make up for the bullets required to kill it.

Inspiration and development
An early version of the zombieman appears in the IWAD file of Doom 0.4, although the sprite does not appear in the game. The sprite is almost identical to the Doomguy; it is slightly lighter in color, and has crudely drawn square red eyes (to show that it is possessed). The only frame is a full frontal view, with no rotations. In Doom 0.5, however, the sprite is virtually identical to the finished version.

Data



 * 1) This table assumes that all calls to P_Random for damage, pain chance, blood splats, and bullet dispersal are consecutive. In real play, this is never the case: counterattacks and AI pathfinding must be handled, and of course the map may contain additional moving monsters and other randomized phenomena (such as flickering lights). Any resulting errors are probably toward the single-shot average, as they introduce noise into the correlation between the indices of "consecutive" calls.
 * 2) The target must be close enough to compensate for the monster's inaccurate aim.
 * 3) Assumes that direct hits are possible, which does not occur in any stock map.

Appearance statistics
In the IWADs the zombieman is first encountered on these maps per skill level:

The IWADs contain the following numbers of zombiemen per skill level:

PlayStation Doom
In PlayStation Doom, their gunshot damage is increased somewhat, up to a maximum of 24. The manual also lists the name of this enemy type as "Former Soldier", though he retains his original name of "Zombieman" in the game ending sequence.

Doom 64
In Doom 64, the zombieman's a visual appearance is similar to that in vanilla Doom, but instead their rifles look more like shotguns and their suits are colored blue-grey. They first appear in MAP01: Staging Area. Also, as in PlayStation Doom, their gunshots deal somewhat more damage than the originals.

Doom RPG
In Doom RPG, the zombieman appears as the "zombie" monster class. There are three different forms, identified by color:
 * Zombie private (brown)
 * Zombie lieutenant (blue)
 * Zombie captain (normal colors)

They are weak against axe attacks.

Trivia

 * In Doom II for Game Boy Advance, a red blood splatter, half-way covered in green, appears in the zombieman's death animation.
 * The bullpup-style rifle carried by the zombieman matches the one carried by the player sprite, and is likely an in-game conception of Tom Hall's Doom Bible idea for the "machine pistol," which was eventually implemented as the assault rifle which appears in the Doom 0.4 beta.
 * Some of the zombieman's rotation sprites are missing from the IWAD, presumably for space reasons. Doom mirrors the existing sprites horizontally to compensate for the missing rotations, causing the direction of the enemy's rifle to "switch sides" occasionally while walking. The missing rotations were later released by John Romero.